A typical circuit board includes a section of printed circuit board (PCB) material (layers of conductive and non-conductive material sandwiched together), circuit board components, and a set of connectors. In general, the section of circuit board material provides (i) structural support for the circuit board components and the set of connectors, and (ii) a set of conducting paths (e.g., etch runs, power planes, etc.) that electrically connect with the circuit board components and the set of connectors. The board components typically mount to the surface of the circuit board section and perform particular operations (e.g., instruction execution, data storage, data formatting, data transceiving, signal processing, etc.). Examples of circuit board components include integrated circuits (ICs), resistors, and capacitors. The set of connectors typically resides along a circuit board edge and enables the circuit board to exchange signals with other components (e.g., a backplane, another circuit board, a disk drive, etc.).
Some circuit boards include an extra connector that enables a user to directly access particular circuitry on the circuit board. For example, a circuit board can include a PCB connector that enables a user (e.g., a test or design engineer of a circuit board manufacturer) to connect a set of oscilloscope probes to the circuit board in order to sample signals for testing and debugging purposes. As another example, a user can connect a computer to the circuit board using a cable in order to program the particular circuitry (e.g., Field Programmable Gate Arrays), and/or test and debug that circuitry.
Furthermore, some specialized interface circuit boards include an extra connector to exchange one or more input/output (I/O) signals with an external device. For example, a printer interface circuit board typically includes a standard D-Subminiature (or D-Sub) connector for providing a printer signal to a printer. The printer typically includes a D-Sub connector as well. A user can then connect the D-Sub connector of the printer interface circuit board to the D-Sub connector of the printer using a standard printer cable (i.e., a cable having complementary D-Sub connectors at each end) thus enabling the printer to receive the printer signal from the printer interface circuit board.
Unfortunately there are deficiencies to the above-described conventional approaches to accessing a circuit board. For example, users typically prefer working with standard parts since such parts are readily available. Accordingly, users often prefer working with D-Sub cables since computer manufacturers typically provide computers having D-Sub connectors as I/O ports, and since D-Sub cables are readily available. That is, a user wishing to access circuit boards (e.g., circuit boards under test) using a computer having a D-Sub connector typically will prefer that the circuit boards have D-Sub connectors allowing that user to use a standard D-Sub cable (i.e., a D-Sub cable having D-Sub connectors at each end). Unfortunately, circuit board manufacturers typically do not attach D-Sub connectors to their non-interface circuit boards because such connectors are relatively large, i.e., because such connectors are bulky and have relatively large footprints requiring a relatively large amount of circuit board area and structural support compared to other connectors such as PCB connectors. That is, although the manufacturers of some I/O interface circuit boards (e.g., the manufacturers of printer interface circuit boards, Universal Serial Bus (USB) interface circuit boards, etc.) attach standard D-Sub connectors to their circuit boards, most other circuit board manufacturers may be unwilling to attach D-Sub connectors to their circuit boards simply for testing or debugging purposes.
However, some circuit board manufacturers may be willing to attach PCB connectors to their circuit boards for testing and debugging purposes. Users (e.g., an engineer or technician of a circuit board manufacturer) wishing to connect a computer to a circuit board having a PCB connector can customize a cable by cutting off the D-Sub connector from one end of a standard D-Sub cable, and fastening a PCB connector in its place. Then, the user can plug the remaining D-Sub connector of that cable into the D-Sub connector of the computer, and plug the newly fastened PCB connector of that cable onto the PCB connector of the circuit board in order to access signals on the circuit board, e.g., in order to test and debug the circuit board.
Unfortunately, the user may find using a customized cable to be cumbersome and time consuming when testing multiple circuit boards. That is, the user can initially run the customized cable between the test computer and the circuit board under test, and then plug in the D-Sub connector of the cable into the test computer and the PCB connector onto a first circuit board. In order to test another circuit board, the user must disconnect the PCB connector of the cable from the first circuit board and plug the PCB connector onto the next circuit board. The task of disconnecting the end of the cable from one circuit board and plugging it into another may require a substantial amount of user time and effort, particularly when the user is testing many circuit boards or when the user must frequently alternate between a fixed set of circuit boards individually (e.g., alternate among four circuit boards under test).
In contrast to conventional approaches to accessing circuit boards by (i) mounting D-Sub connectors to the circuit boards or (ii) mounting PCB connectors to the circuit boards and using a customized cable having a D-Sub connector on one end and a PCB connector on the other, some embodiments of the invention are directed to circuit board accessing techniques which use an adaptor having a circuit board connector and a switchbox connector (e.g., a D-Sub connector). A user (e.g., an engineer) can access a circuit board having a circuit board connector using a computer equipped with a switchbox connector by connecting the adaptor to the switchbox connector of the computer and then running a standard cable having a circuit board connector at both ends between the circuit board and the adaptor into order to enable the computer to communicate with the circuit board. Alternatively, the user can attach the circuit board connector of the adaptor to the circuit board connector of the circuit board, and then run a standard switchbox cable (e.g., a D-Sub cable) between the adaptor and the computer in order to enable the computer and the circuit board to communicate with each other. Other configurations enable the user to easily connect with and access multiple circuit boards using a connection system having multiple adaptors as well as other components.
One embodiment of the invention is directed to a connection system that includes a multi-port switch, multiple adaptors and multiple cable assemblies. The multi-port switch includes a primary port, multiple secondary ports, and a controller (e.g., a turnable knob) which is configured to connect the primary port individually to the multiple secondary ports. Each adaptor mates with one of the multiple secondary ports of the multi-port switch and includes (i) a circuit board connector having a set of circuit board connector contacts, (ii) a switchbox connector having a set of switchbox connector contacts, (iii) a fastener which physically fastens the circuit board connector of that adaptor and the switchbox connector of that adaptor together, and (iv) a set of conductors that electrically connects the set of circuit board connector contacts to the set of switchbox connector contacts. Each cable assembly includes a first circuit board connector which is configured to mate with the circuit board connector of an adaptor, and a second circuit board connector which is configured to connect with a circuit board. Such a connection system is suitable for accessing multiple circuit boards (e.g., by setting the controller of the multi-port switch in order to access any of the circuit board individually).
In one arrangement, the circuit board connector of each adaptor further includes a circuit board connector housing that defines a circuit board connector footprint, and the switchbox connector of each adaptor further includes a switchbox connector housing that defines a switchbox connector footprint. In this arrangement, the circuit board connector footprint is preferably smaller than the switchbox connector footprint. Accordingly, a manufacturer wishing to utilize the connection system can also save space by avoiding the use of the D-Sub connector on circuit boards but instead use the PCB connector which has a smaller footprint.
In one arrangement, the circuit board connector housing of the circuit board connector of each adaptor defines a circuit board mounting interface and a connector interface that is at a right angle to the circuit board mounting interface. The switchbox connector housing of the switchbox connector of that adaptor defines a cable attachment interface and a D-Subminiature connector interface. The set of conductors of that adaptor extends from the circuit board mounting interface defined by the circuit board connector housing to the cable attachment interface defined by the switchbox connector housing. The right angle configuration of the switchbox connector enables (i) the circuit board mounting interface defined by the circuit board connector housing and the cable attachment interface defined by the switchbox connector housing to be close together, and (ii) the set of conductors to be fairly short.
In one arrangement, for each of the multiple adaptors, the set of circuit board connector contacts includes 10 soldering pins. Additionally, for each of the multiple adaptors the switchbox connector housing is configured to hold, as the set of switchbox connector contacts, up to 25 crimps. Furthermore, for each of the multiple adaptors, the set of conductors includes (i) a first wire that electrically connects a transmit signal pin of the 10 soldering pins to a transmit signal crimp which inserts into a transmit signal crimp location of the switchbox connector housing, (ii) a second wire that electrically connects a receive signal pin of the 10 soldering pins to a receive signal crimp which inserts into a receive signal crimp location of the switchbox connector housing, and (iii) a third wire that electrically connects a ground signal pin of the 10 soldering pins to a ground signal crimp which inserts into a ground signal crimp location of the switchbox connector housing. This arrangement enables preservation of a standard contact layout in each of the connectors (e.g., the RS-232 layout).
In one arrangement, the fastener of each adaptor includes an adhesive (e.g., glue) that attaches the circuit board connector housing of the circuit board connector of that adaptor to the switchbox connector housing of the switchbox connector of that adaptor. This arrangement enables the two housings to be attached using a very simple and low cost means.
In one arrangement, each adaptor further includes a shrink wrap coating that, in combination with the circuit board connector housing of the circuit board connector of that adaptor and the switchbox connector housing of the switchbox connector of that adaptor, physically insulates the set of conductors of that adaptor. Accordingly, the adaptor is less prone to damage from inadvertent handling or contact.
In one arrangement, the connection system further includes an electronic device (e.g., a computer) that electrically connects to the primary port of the multi-port switch, and multiple circuit boards that electrically connect to multiple secondary ports of the multi-port switch. In this arrangement, the user can individually access (e.g., test) the circuit boards using the electronic device.
The features of the invention, as described above, may be employed in connection systems (e.g., testing and debugging systems), devices and methods as well as other computer-related components such as those of EMC Corporation of Hopkinton, Massachusetts.